Tuomas Leikola wrote:
On 9/10/06, Bodo Thiesen <bothie@xxxxxx> wrote:
So, we need a way, to feedback the redundancy from the raid5 to the
raid1.
<snip long explanation>
Sounds awfully complicated to me. Perhaps this is how it internally
works, but my 2 cents go to the option to gracefully remove a device
(migrating to a spare without losing redundancy) in the kernel (or
mdadm).
I'm thinking
mdadm /dev/raid-device -a /dev/new-disk
mdadm /dev/raid-device --graceful-remove /dev/failing-disk
also hopefully a path to do this instead of kicking (multiple) disks
when bad blocks occur.
Actually, an internal implementation is really needed if this is to be
generally useful to a non-guru. And it has other possible uses, as well.
if there were just a --migrate command:
mdadm --migrate /dev/md0 /dev/sda /dev/sdf
as an example for discussion, the whole process of not only moving the
data, but getting recovered information from the RAID array could be
done by software which does the right thing, creating superblocks, copy
UUID, etc. And as a last step it could invalidate the superblock on the
failing drive (so reboots would work right) and leave the array running
on the new drive.
But wait, there's more! Assume that I want to upgrade from a set of
250GB drives to 400GB drives. Using this feature I could replace a drive
at a time, then --grow the array. The process for doing that is complex
currently, and many manual steps invite errors.
--
bill davidsen <davidsen@xxxxxxx>
CTO TMR Associates, Inc
Doing interesting things with small computers since 1979
-
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
